LONDON, England (CNN) -- Troubled singer Amy Winehouse has been admitted to a London hospital after suffering a bad reaction to medication, her representative said Tuesday.

Amy Winehouse has undeniable talent, but has become better known for her wild behavior.

Winehouse, 25, went to the private London Clinic on Sunday, said her spokesman, Chris Goodman. He said Winehouse's medication made her ill and her doctors asked her to come in so they could investigate.

Goodman did not disclose what type of medication was involved, saying only it is part of her "ongoing treatment." It was not clear Tuesday whether she had been discharged.

Yesterday Winehouse's husband Blake Fielder-Civil lost his appeal against his 27-month jail term for assault and perverting the course of justice.

Earlier this month he was moved from prison to a drug rehabilitation unit.

The Grammy-winning Winehouse has suffered a string of health problems in recent years, many related to her battles with drug addiction.